Solar Energy: The Ultimate Renewable Resource - PowerPoint PPT Presentation

Loading...

PPT – Solar Energy: The Ultimate Renewable Resource PowerPoint presentation | free to download - id: 80c481-MzliM



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Solar Energy: The Ultimate Renewable Resource

Description:

Title: Solar Energy: The Greatest Renewable Resource Author: Preferred Customer Last modified by: CUSD95 Created Date: 10/22/2002 11:48:07 PM Document presentation format – PowerPoint PPT presentation

Number of Views:119
Avg rating:3.0/5.0
Slides: 13
Provided by: Preferr1684
Learn more at: http://www.lz95.org
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Solar Energy: The Ultimate Renewable Resource


1
Solar Energy The Ultimate Renewable Resource
2
What is Solar Energy?
  • Originates from nuclear fusion reactions in the
    sun

Nuclear Fusion Video (1.5")
3
Advantages and Disadvantages
  • Advantages
  • Chemical/radioactive pollutants remain on sun
  • Energy reaching the earth is incredible. By one
    calculation, 30 days of sunshine striking the
    Earth have the energy equivalent of the total of
    all the planets fossil fuels, both used and
    unused!
  • Disadvantages
  • Sun does not shine consistently.
  • Solar energy is a diffuse source. To harness it,
    we must concentrate it into an amount and form
    that we can use, such as heat and electricity.

4
Putting Solar Energy to Use Heating Water
  • 2 methods of heating water passive (no moving
    parts) and active (pumps)
  • In both, a flat-plate collector is used to absorb
    suns energy to heat water
  • Water circulates through the closed system due to
    convection currents
  • Tanks of hot water are used as storage or to heat
    swimming pools

5
Heating Water Active System
Active System uses antifreeze so the liquid does
not freeze if outside temp. drops below freezing.
Active Water Heating Animation
6
Passive Heating of Living Spaces
  • Best design of a building is for it to act as a
    solar collector and storage unit. This is
    achieved through three elements insulation,
    collection, and storage.
  • Efficient heating starts with proper insulation
    on external walls, roof, and the floors. Doors,
    windows, and vents must be designed to minimize
    heat loss.
  • Collection south-facing windows

7
Heating Living Spaces
Passive Solar
Passively heated home in Colorado
8
Heating Living Spaces
  • Passively heated homes use 60-75 of solar energy
    that hits its walls and windows
  • A well-designed passive solar home can reduce
    energy bills by 75 with an added construction
    cost of only 5-10
  • About 25 of energy is used for water and space
    heating

Passive Solar Home Design Video (5")
9
Solar-Thermal ElectricityParabolic Dishes and
Troughs
  • Solar energy ? electricity
  • Some solar power plants (see picture from Mojave
    Desert) use curved mirror called PARABOLIC TROUGH
    to focus sunlight on a pipe running down center
    of mirror.
  • Mirror focuses sunlight onto the pipe, causing
    the water to boil and produce steam. Steam can
    then be used to turn a turbine to make
    electricity.
  • Rows of solar mirrors are arranged in "solar
    thermal power plants. They make electricity for
    more than 350,000 homes.

10
Solar-Thermal ElectricityPower Towers
  • Sunlight is reflected off 1,800 mirrors
    (HELIOSTATS) circling the tall tower.
  • Fluid (liquid sodium) is heated by sun's rays.
    The fluid is used to boil water ?make steam ?
    turn a turbine and generator
  • This experimental power plant is called Solar II.
    It was built in California's desert.
  • Scientists say larger central tower power plants
    can make electricity for 100,000 to 200,000
    homes.
  • Solar Power Towers Animation (2.5")

11
Direct Conversion into ElectricitySolar Cells or
Photovoltaic Energy
  • Sunlight converted directly to electricity using
    solar cells
  • Solar cells also called photovoltaic cells (PV
    cells) and can be found on many small appliances,
    like calculators, and even on spacecraft
  • First developed in 1950s for U.S. space
    satellites.
  • Made of silicon, special type of melted sand
  • Sunlight strikes solar cells and electrons (red
    circles) are knocked loose. They move toward
    treated front surface (dark blue color). When the
    two surfaces are joined by a wire, a current of
    electricity occurs between negative and positive
    sides.
  • Solar cells ? PV module ? Array.
  • Some arrays are set on special tracking devices
    to follow sunlight all day long.

Photovoltaic Energy Video
12
  • Electrical energy from solar cells can be used
    for lights/appliances
  • Solar energy can be stored in batteries to light
    roadside billboards at night
  • Energy can be stored in a battery for emergency
    roadside telephones where no phone wires are
    around
  • Some experimental cars also use PV cells. They
    convert sunlight directly into energy to power
    electric motors on the car.
  • Solar cells are used in satellites in outer
    space. Here's a picture of solar panels extending
    out from a satellite.

Rooftop PV Modules
About PowerShow.com